[llvm] [DebugInfo] Handle followup loop metadata in updateLoopMetadataDebugLocations (PR #157557)

[Stephen Tozer via llvm-commits]

https://github.com/SLTozer commented:

One small question - is a "visited" list necessary to avoid updating the same metadata multiple times? It might not be an issue, or even something that already happens, but it does seem more likely that we could end up updating the same DILocation multiple times from your example.

Aside from that, and some inline questions, this LGTM.

https://github.com/llvm/llvm-project/pull/157557